THE TRACK OF THE TETRAPOD – By Diarmuid Ring
Fadó, fadó ó shin ní raibh Éire mar ata sí anois….”.
This was the first part of the first sentence of the first history book I had at my alma mater, the “Foot” school, labelled with alien effrontery “Knightstown National School”. It is only part of that book I can quote verbatim and that hardly qualifies me to write an essay on a four footed animal that swam ashore at Dohilla on the Northern shores of Valentia Island 350-370 million years ago. Dohilla is an interesting place and it’s a pity its history will hardly be written. From its almost perfect amphitheatre the views of mountains and seas, bays and inlets can hardly be described in words alone, only an old master with paint and canvas could do justice to it.
Some of the defeated Spanish Armada ships came this way as evidenced by the find nearby of a Spanish navigational instrument of the period called an “Astrolabe”. Perhaps the dangerous beach called “Tra na Luinge” has some sinister significance? Cromwell’s officers and men came here too and built a fort and installed cannon at a point now called Cromwell-Fort Point to deter uninvited guests. And Mr. Petty, later Lord Landsdowne, came in due course soon after, or his clerks did, to measure every square foot of land, and enter it in the “Book of survey and distribution”. One day Paul Jones, “The sailor whom England feared”, hoved – to off Reen-garbh in that cranky old tub the “Bonhomme Richard” the French Government lent him. He took onboard two island fishermen and invited them, perhaps shanghaied would be a better word, to
However having said that, once the paw marks were pointed out to me on site, even my untrained eye had no problem at all in identifying them as the footprints of an animal wandering across a muddy sandy silt, wet enough to retain the impression indefinitely until the sand solidified into stone. They were discovered in 1992 and identified as the footprints of a “Tetrapod”, a pre-dinosaur creature, which resembled a large lizard or salamander, one of the earliest known vertebrae life forms that crawled out of the sea to live on land at what is regarded as a critical moment in evolution.
Tetrapods died out about 320 million years ago, to be replaced by a new wave of different amphibians, distant ancestors of dinosaurs which first appeared about 200 million years ago. Our Dohilla friend left approximately 150 footprints in total and calculations from the spacing of these footprints suggest the animal was one metre in length, perhaps not unlike our modern day otter?. There are two types of footprints which differ in size, the smaller prints probably represent “hand” impressions and the larger ones “foot” impressions (fore-legs and hind-legs?). When you consider that trackways of this age are very rare and this is the first discovery of its kind in Europe, and the largest in the World, is it any wonder that Geologists are very excited about the Dohilla find and it is getting world-wide publicity. A few weeks ago we had a letter from a Valentia Island man working in the United Arab Emirates enclosing a cutting from the “Khaleej Times” about the Tetrapod and demanding to
accompany him on his voyage up the West coast.
One came back and the family was subsequently known as the Murphy-Jones.
The slate quarry in Dohilla, with its massive heaps of spoil, stands a mute testament to the industrial revolution and the small unmarked block house at Cuas na Bó, just West of Traig Fhionain pier, once saw the trans-atlantic telegraph cables start their long journey to Hearts Content, New Foundland. Each would warrant a couple of full-length history books in their own right. But a consolation for abandoned quarries and telegraph cables are the state of the art new buildings of the Valentia Radio Station, sitting atop the cliff at the western end of Dohilla by Reen a Dreoilin Point and Cuas a Horna (Tornach?).
But back to our hairy or furry Amphibious friend. I have studied Mr. I. Stossel’s admirable discourse in the journal of the Geological Society several times, but alas, I am academically unqualified to even comment on it. For instance, in discussing “Strain analysis” he says “Southern Ireland lies within the Phenohercynian zone of the Variscan Orogen, i.e. in the northern external zone, where cleavage development, folding and thrusting occurred during deformation. The trackway is on the southern limb of a mesosopic anticline which has a wavelength of several hundred metres, and in which the rocks are affected by axial planar, pressure solution cleavage…etc”. This is the language of academia, which is over my head unfortunately.
know what the hell was going on in Valentia!!
The prestigious American magazine, National Geographic sent a photo-grapher to visit the site last September and he spent a fortnight trying to get suitable photographs, apparently he had problems getting the light right. He advised me that they would be published next year, more than likely in the June or July edition. In the meantime the Geological Survey of Ireland advise us that the Dohilla find will feature as part of the Earth Science exhibitions planned for the next phase of development of the National Museum of Ireland at Collins Barracks in Dublin.
In conclusion, it was the action of the sea that exposed the track-way and unfortunately this erosion is continuing. In the fullness of time the footprints will become blurred and eventually disappear altogether, not in our time, or even our children’s time, but certainly a very short time in geological time. But hold it, all is not yet lost. With the help of a grant from the Heritage council, two casts of part of the trackway have been taken and a realistic model made in polyester resin. One of the models is in the Geology Department of University College Cork, but don’t go dashing off to Cork. We have the other model in the Valentia Heritage and in due course it will be suitably mounted and put on display.
Reproduced with kind permission of The Valentia Review.